I went through excatly the same with my DS. It was a sodding nightmare. Don't deny her milk, as I found from bitter experience that it doesn't work. In fact, I found that in the end, it was best to give him a milk feed and then try him with his food, as it would often make him more relaxed.
What foods are you trying her with? My ds didn't like bland tasting foods to begin with. I tried all the single purees nonsense as well. In the end, I got fed up, and gave him some of what I was eating one day and lo and behold, he chomped it down and he hasn't looked back since! (He was nearly 9 months old by this point)
I discovered from this first proper taste (ratatouille and potato was the v first thing he ate) that stronger tasting foods were always a winner.
Have you also made sure that the purees etc you are trying DD with are smooth enough? Some babies gag if there is the tiniest lump in, and other don't, so you might need to experiment.
Finger food is a bit of a hit and miss affair at 8 months. Sometimes, I found that DS would happily suck on whatever I gave him, others he would have a great laugh throwing them on the floor/at me. I find that the most successful ff is toast with a smidge of butter. It keeps DS amused for hours, as when he has got bored of eating it, it provides him with hours worth of toast modelling/weaponry.
It sounds like you are doing everything right. I know how bloody demoralising it is having a baby that wont touch anything when it seems like friend's babies of the same age are dining out every night at the Savoy and tucking into 4 course meals. The best thing you can do is not to make a big dael out of it, as your baby is probably picking up on the fact that htis issue is a sure fireway to get you undivided attention.
Let your DD just experiment with her food and she WILL do it in her own time, I promise. This is coming from the woman who had screaming abb dabbs in the kitchen because her son wouldn't eat one spoonful of the lovingly prepared carrot mush that I was trying to feed him (frozen in the obligatory ice cubes)
Another chestnut which I found worked quite well, was to eta a bowl of mush too, with a tiny plastic spoon (I did look at tit, mind) and he wanted some. I do kind of regret this approach now, as the little sod keeps trying to steal my lunch. Grrrrr.
Anyway, I will stop talking crap now, (lack of sleep makes me ramble) Just sit tight. There's no magic formula, I am afraid. She won't starve. Promise. At this age, they don't really need a lot of food to get by. If she is being BF, she is getting everything she needs. My DS's weight gain slowed quite a bit when he was about this age, but it has evened out now. (He's just turned 1) The bset advice I can give you is don't force it.
Ramble over. Sorry, I went on a bit.